Solar Power - An Emerging Technology by R N Kumar (GM, HOD Protection and Testing) S Naved Masood

1. Solar Power- An EmergingTechnologybyR N Kumar (GM, HOD Protection and Testing) S Naved Masood (Executive, Protection and Testing)

2. Introduction • India receive 4–7 kWh/m2/day solar radiation with 250–300 sunny days in a year. • Highest annual radiation • Western Rajasthan • Lowest annual radiation • North-eastern region • Delhi has a share of around 4.5 kWh/m2/day • Introduction to Solar Power • Basic Fundamentals • Solar Power at NDPL • 1 MW Solar Power Plant at Keshav-Puram. • Interaction of Installed Plants • Upcoming Projects 4

3. Benefits of Solar Energy • No contribution to global warming or greenhouse effects • Fuel is freely available. No dependence on any other fuel. • Almost negligible maintenance. • Generate the energy you need and where you need it. • Reduced vulnerability to power loss when it acts as backup. • Systems are easily expandable • Solar power is silent power. No contribution to noise pollution 4

4. Harnessing the Solar Energy 4

5. Photo Voltac Cells 4

6. The Transformation 4

7. A Solar Module 4

8. Types of Solar Modules • Mono-crystalline silicon: Most efficient technology (efficiencies of around 18% (commercial) to 28% (research) • Multi-crystalline silicon: Cheaper than mono-crystalline silicon but also less efficient. Research cells approach 24% efficiency, and commercial modules approach around 16% efficiency. • Thin film: • Cheaper than crystalline silicon but less efficient. • Various materials (amorphous silicon, Cadmium Telluride, Copper Indium Di-Selluride (CIS) Selection of the technology depending on: site, irradiation, temperature, costs vs. efficiency etc. 4

9. Efficiency of Solar Cells 4

10. Worldwide Installed PV Supply 4

11. I-V Curves at various levels of Irradiance 4

12. Maximum Power Achievement Point 4

13. Solar Power at NDPL • CENPEID- 12.2 KW • Grid Interactive with dedicated load of 1.2 kW • Inverter capacity 10kVA • Auto synchronization & Isolation from grid through PCU • Remote communication using TCP-IP implemented • Metering with GSM • Project Cost : ~ Rs. 50 lakh • Project Execution Duration : ~10 weeks 4

14. Solar Power at NDPL • Board Room - 3.96KW • Direct Grid Interactive with dedicated load of 0.5 kW - without batteries • Auto synchronization & isolation from grid through PCU • Metering & Communication through CDMA being experimented. • Project Cost /Duration : 20 lakh/ 8 Weeks 4

15. Solar Power at NDPL • NDPL Central Stores - Keshavpuram • Capacity : 1 MW • - First MW size Solar Project by NDPL • - Comprising 4 x 250 kVA grid connect modules • - PV solar panels over covered shed area ~1.5 Acres • SCADA controlled • Project Cost : 19 Cr • Raised Civil Structure : 6 Cr • Solar Panel & Elec. Equipment : ~13 Cr 4

16. 1 MW Plant at Keshav-Puram • 1 MW Solar Power Plant has been commissioned successfully in NDPL Central Stores : Keshav-Puram • Protection Department has provided support to the BD team for the following activities: • Scheme development • Panel wiring • Actualization of Inter panel schemes • Mapping of External trip command to RMU’s shunt trip coil • Retrofitting of RMU (110V DC shunt trip coil to 24V DC) to match control wiring voltage 4

17. 1 MW Plant at Keshav-Puram • A total of 5576 nos. of Mono-crystalline Solar Modules are used. • Each Module is of rating 180Wp rating that combines to give around 1MWp Power. • 17 Modules are connected in an array. • 82 Strings are connected in parallel to each inverter for an output of 250KVA. 4

18. 1 MW Plant at Keshav-Puram 4

19. Control Schematics at 1 MW Plant • 415V/11KV 1250 KVA Transformer is fitted with OTI, WTI, Buchholz and MOG to cater its internal faults. • Alarms through OTI, WTI, Buchholz and MOG are routed to the PCU as well as to a Buzzer. • The tripping contacts of above are routed to a shunt trip coil in RMU for isolation of Transformer in case of any internal fault. • Interaction among Installed Plants • ABB’s Micro-SCADA software will be used for Control & Monitoring of the Solar Plants • The Inverter at each station shall communicate with this SCADA software over the IEC 60870-5-104 protocol through GPRS communication • A GPRS router will be installed at each Remote Solar plant and a Lease Line router at control center. • The solar plant data will be available over IEC 104 for further transfer to existing NDPL SCADA. 4

20. Interconnection of Solar Plants 4

21. Major Upcoming Projects • Distributed Solar Roof –Top project • 100MW (Peak) : 5KW/10 KW @ 20000/10000 roof tops • 50% subsidy proposed to Govt. • Go-NCTD indicated support - awaited • NDPL – Tata Power Joint Project in Rajasthan • Exploring feasibility • 500 MW (100MW NDPL + 400MW TPC ) • 2000-2500 acres of land to be acquired around Udaipur and Jaiselmer • Upcoming Projects of Solar Power at NDPL • 25 KW at DERC office • Design / Engineering Completed • Techno-Commercial Evaluation • MNRE approval received on DPR • 25 KW at CM office • Design / Engineering Completed • Techno-Commercial Evaluation • MNRE approval received on DPR • 200 KW at NDPL colony Narela • Techno-Commercial Evaluation • MNRE approval received on DPR 4